PeachParts Mercedes-Benz Forum - View Single Post

jay_bob · #74 10-01-2018, 01:50 PM

I thought the US market W124 and S124 (1987 only) were fitted with a 6 cyl OM603 up until 1989. From 1990-1994 they got the 5 cyl OM602 and were badged 300D-2.5.
In 1995 they got the N/A OM606 engine that was then used in the W210.

From what I have learned the OM603s had the EDS but it only worked on the ARF valve on the turbo. The wastegate was pressure operated. They had a pressure switch in the manifold that opened a switchover valve in the manifold to ALDA line that dumped the boost if it became excessive.

Starting in 1990 with the 2.5 liter/5 cylinder OM602 they expanded the electronic controls by adding a MAP sensor and vacuum operated wastegate.

So chances are if the OP has a transplanted engine from a W124 it is likely from an 87 to 89 model with the pressure operated wastegate. If the person doing the swap was diligent they would have brought over the EDS computer from the W124 donor along with all the associated control hardware.